Three primary colors of light refer to red, green and blue, and may be mixed according to a certain ratio to present light of various colors. The screen of a color television is composed of light emitting spots of red, green and blue. The three primary colors may be mixed according to different ratios and intensities to form various colors in nature, and a color is expressed by brightness and chroma together.
The chroma of an image displayed by a display device is determined by the chroma value in an image data signal output by a signal source. However, for a display device which needs to use a backlight module (including a light source), the performance of the light source may inevitably influence the chroma of the image displayed by the display device.
An existing method for displaying an image by a display device includes steps of:
step 1: acquiring, by an image signal processor, chroma values, output by a signal source, of all sub-pixels needed when the display device displays the current frame of an image; and
step 2: driving, by the image signal processor, the display device to display the current frame of the image according to the chroma values of all the sub-pixels.
The applicant has discovered that, the existing method for displaying an image by a display device has the following shortcomings:
1. Hardware is adopted in the prior art to adapt to an image data signal, namely hardware is selected according to the chroma range of the image to be displayed. However, processing errors inevitably exist in industrial processing of the hardware, so the hardware can only ensure the consistency of the theoretical chroma and the practical chroma within a certain range but cannot ensure the complete consistency of the theoretical chroma and the practical chroma.
2. To ensure the color display effect of the display device, the limitation to the chroma range of the display device is narrow, so that the requirement for control precision in the industry of display devices and accessories thereof is high. The range of available materials for manufacturing the display device is small, so that the cost of the display device is high. For example, due to narrow chroma range of light source required in the prior art, the yield of the light source (e.g. an LED light source) is low, and then the cost of the display device is correspondingly high.
3. To meet the requirement for the chroma of the LED light source while improve the yield of the LED light source, LED Light Bars are mostly produced and used in an LED lamp mixed BIN manner, so that the problems of non-uniform chroma in picture and the like appear.
4. With the increase of service time of the display device, the performance of the light source or individual components attenuates or varies, so that the chroma of the image displayed by the display device is changed, and then the user experience is influenced.
5. Because color filters, manufacturing processes and the like used for producing liquid crystal panels in various manufacturers are different and the requirements for the chroma of the light source are inconsistent, components such as the light source and the like may not be universal in the industry.
To sum up, the existing method for displaying an image by a display device has the shortcoming that the practical chroma is inconsistent with the chroma (namely theoretical chroma) acquired from the image data signal output by the signal source or the chroma difference is beyond an error range, so that the display effect of the display device is seriously influenced.